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排序方式: 共有1739条查询结果,搜索用时 15 毫秒
81.
This study assessed the altitudinal variations in the anthocyanin and isoflavone contents of six black seed coated soybean [Glycine max (L.) Merrill] cultivars. The black soybean cultivars Heugcheong, Seonheuk, Geomjeong 1, Geomjeong 2, Cheongja 2, and Cheongja 3 were planted at Milyang (12 m above mean sea level — low altitude) and Muju (600 m — high altitude), Korea on 10 June 2005 and 2006. The total anthocyanin and isoflavone contents and individual components were investigated by reverse-phase high performance liquid chromatography (HPLC). All black soybean cultivars cultivated in high altitude possessed significantly higher total anthocyanin (p < 0.01) and isoflavone (p < 0.01) contents than those grown in low altitude. For anthocyanin composition, cyanidin-3-O-glucoside, cyanidin-3-O-galactoside, and peonidin-3-O-glucoside contents were significantly higher while delphinidin-3-O-glucoside contents was significantly lower at high altitude. The composition of individual isoflavones, 6″-O-malonyldaidzin, and 6″-O-malonylgenistin contents significantly increased at high altitude.  相似文献   
82.
The pear cultivar ‘Osa-Nijisseiki’ (S2Ssm 4; sm = stylar-part mutant) has been used as a parent to breed self-compatible cultivars that produce excellent fruits. However, determination of the self-compatibility of ‘Osa-Nijisseiki’ offspring requires a lot of time, 6 years or more, by conventional cross breeding. We have designed a rapid reliable method for the identification of self-compatible varieties of ‘Osa-Nijisseiki’ offspring based on the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with S-allele specific restriction endonucleases. By using this method, 8 self-compatible varieties were selected among 16 selections resulting from a cross between the self-compatible cultivar ‘Osa-Nijisseiki’ (S2Ssm 4) and the self-incompatible cultivars ‘Niitaka’ (S3S9), ‘Whasan’ (S3S5), ‘Chuwhangbae’ (S4S6). The S-genotypes of 16 ‘Osa-Nijisseiki’ offsprings were also determined. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
83.
芥菜型油菜黄黑种皮多酚差异的紫外-可见光谱研究   总被引:4,自引:0,他引:4  
曾盔  刘忠松  龙桑  严明理 《作物学报》2007,33(3):476-481
以芥菜型自交系黄黑油菜种皮为材料,研究了其多酚提取液的紫外-可见吸收光谱, 测定了芥菜型油菜黄黑种皮样以没食子酸和茶儿茶素标准计的多酚含量,发现黄种皮的多酚含量约为黑种皮的90%,显著区别于甘蓝型油菜的10%,因此多酚含量高可能是芥菜型黄籽油菜性状稳定的根本内因。基于香草醛试验,推测黑种皮中含有3-OH的黄烷醇类多酚,而黄种皮中没有。基于加入位移试剂后特征吸收谱带Ⅰ与Ⅱ的位移方向与大小,推测黄酮醇类多酚A环在黄种皮中可能主要为单酚羟基,而在黑种皮中可能主要为邻二酚羟基结构。这种多酚分子的结构差异可能是形成芥菜型油菜黄黑种皮色泽差异的主要原因。  相似文献   
84.
不同改良剂对铅污染砖红壤的修复效果   总被引:6,自引:0,他引:6  
在未污染的花岗岩砖红壤中加入重金属Pb,平衡两周后在污染土壤上施用不同水平的钙镁磷肥、牛粪、钙镁磷肥+牛粪等改良剂,以小白菜作为指示作物,根据小白菜生长动态变化和收获后生物量、Pb吸收量、土壤pH、土壤中有效Pb含量等理化性质的差异,来评价各种改良剂对Pb污染砖红壤的改良效果,以便为海南花岗岩砖红壤Pb污染修复提供理论依据。实验结果表明:各改良剂对Pb污染土壤都有一定的修复效果,不同程度的减轻了小白菜的毒害症状,其中钙镁磷肥与牛粪配施处理效果最好,该处理的小白菜不仅生物量高,而且Pb含量较低;其次是钙镁磷肥处理,而改良效果最差的是牛粪,其植株叶片不仅稍有黄化症状,且Pb含量较高  相似文献   
85.
酶抑制法检测4种辛辣蔬菜农药残留假阳性消除的研究   总被引:4,自引:0,他引:4  
促进和规范农村土地流转是当前农村全面小康社会建设和新农村建设的重要内容之一。当前,应积极进行农村土地流转的理论分析,促进农村土地流转的法制化,完善政府的引导、管理和服务职能,积极建立和完善农村土地流转机制,建立健全农村社会保障体系。  相似文献   
86.
我国林木种子活力研究进展   总被引:2,自引:1,他引:2  
桑红梅  彭祚登  李吉跃 《种子》2006,25(6):55-59
种子活力是种子学研究中的热点问题,本文针对我国林木种子活力研究的进程与现状进行了系统的总结,对研究中的一些热点问题进行了深入分析讨论,提出了林木种子活力研究目前存在的主要问题及其解决的建议。  相似文献   
87.
魔芋试管微球茎成熟度对其储藏及萌发率的影响   总被引:2,自引:0,他引:2  
种子在母体植株上的干燥过程是种子完成从发育到萌发的一个重要转换点。魔芋组织培养中诱导试管微球茎过程中,在色泽上有1个明显的变化过程。本实验将这个过程分为3个阶段,对不同采收时期的微球茎进行储藏及萌发研究,结果表明,不同采收期的微球茎,储藏后的萌发率具有较大的差异,而且这种差异与魔芋种具有较大的相关性,这种差异与其保水性能有关。同时对试管微球茎收获度对储藏后萌发率影响的机制进行了初步的探讨。  相似文献   
88.
In Brassica oleracea, production of F1 hybrid seeds mainly makes use of the improved Ogura cytoplasmic male sterile (CMS) line. However, reliance on one particular line is a risk, and it would be advantageous to develop other CMS lines. In this study, we transferred Diplotaxis erucoides cytoplasm to B. oleracea cultivars using an alloplasmic B. rapaCMS line as a bridge plant to avoid incompatibility between donor and recipient plants. The new B. oleraceaCMS lines, which were derived by four generations of backcrossing, had small rudimentary anthers with no pollen grain and showed complete male sterility. There was no functional defect in other floral organs, and the ability to receive normal pollen did not appear to be impaired. Moreover, the B. oleraceaCMS lines carrying D. erucoides cytoplasm had larger leaf areas and a normal plastochron. As a consequence, the B. oleraceaCMS lines carrying D. erucoides cytoplasm have the potential to be valuable alternatives for use in commercial B. oleracea hybrid seed production.  相似文献   
89.
This study was carried out to determine the pretreatment effect of proton beam irradiation on germination and pasting properties of starches in two rices. Mature and healthy seeds irradiated with 10 doses (0, 50, 100, 200, 300, 400, 500, 600, 700, and 800 Gy) for determination of LD50 and characteristics of germination were recorded at 14 days after irradiation. The rice seeds irradiated with five doses (0, 50, 100, 200, and 300 Gy) were used to evaluate the irradiation effects of pasting properties of starches. It showed that a lower survival rate in germinated rice seeds was observed above 300 Gy showing 31 and 35% in Ilpum and Hanmaum, respectively. The higher plant height and root length were also recorded in 50 and 100 Gy. Amylose content in proton beam irradiated with 50, 100, 200, and 300 Gy was significantly decreased in two rice cultivars. Peak viscosity, hot peak viscosity, cooling peak viscosity, and setback viscosity decreased with increasing proton beam dose levels. The degree of crystallinity was significantly increased with increasing proton beam dose levels. Consequently, it might be deduced that proton beam irradiation causes changes of starch properties affecting crystalline regions of starch granules, especially at high dosage irradiation.  相似文献   
90.
For the identification of a novel insecticidal protein, a two-dimensional liquid chromatography (PF-2D) system was used in a quantitative proteomic analysis of Xenorhabdus nematophila CBNU strain isolated from entomophagous nematode Steinernema carpocapsae . Protein patterns obtained from minimum and maximum insecticidal activities during cultivation were contrasted, and a novel toxin protein (Txp40) was identified by MALDI-TOF/MS. The DNA sequence of the cloned toxin gene (1089 bp) has an open reading frame encoding 363 amino acids with a predicted molecular mass of 41162 Da. The txp40 identified in this study is most closely related to the known txp40 cloned from X. nematophila EB (ADQ92844) with 94.4% identical sequence residues. Following the expression of the newly identified toxin gene in Escherichia coli , the insecticidal activity of the recombinant toxin protein was determined against Plutella xylostella larvae; a 56.7% mortality rate was observed within 24 h.  相似文献   
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